How a Substack post helped me get a book deal
True story

It started with a Substack note. A year ago, on impulse, I posed this question:
And then I forgot I’d even posted it, so that the next time I opened Substack, maybe 24 hours later, I was shocked by the number of notifications. The note had gone very mildly viral—Substack viral, last of the text-based-internet viral? Enough to raise my eyebrows, anyway. I can count on one hand the number of times I’ve opened any app to see dozens of notifications.
Most of my notes get no response. Zip. Besides, I’ve been pretty quiet here since my life blew up with my son’s diagnosis; spare time has not really been a thing. But this note did something, bucking the trend. In all, it got 2,600 likes, 260 comments, and about 400 new people signed up for this newsletter. A good result for a note, but I didn’t expect anything more to happen. I just started working on the essay.
That’s when I ran into an old problem: the material. Every damn time I tried to write about Mary Shelley—especially her relationship with her lover turned manic pixie nightmare husband, Percy Bysshe Shelley—the piece would rise up out of the sea to destroy whole towns. I’d sit down to write a 1,000-word post and then wake up with 6,000 words. I couldn’t get past the first few affairs. The betrayals. The insane purchases. The debts. The flights of transparently self-serving “philosophical” insight. There was too much to say—too much story, too much wait what yes really?! Focus on the work, or focus on the life? Shelley’s novels are fascinating and endlessly worthy of comment, and her life just as fascinating, maybe more so, while Shelley biography is a saga unto itself.
But I also felt like I needed to deliver on what I promised, so I decided to make it a series and I rushed out a first post, almost exactly one year ago:
A day later, the email came. An agent I’d met a couple years before was in my inbox, asking: Hey, is this a book?
My immediate response was: you know it sure seems to be. I have too much material and too much to say, and also maybe a title and parts of a proposal because, shortly after my Poe book came out in 2021, I realized I wanted to write about Mary—like enough to start sketching out what a book might look like, only to get overwhelmed and put it aside.*
The new agent and I got on Zoom. A friendly chat, an informal pitch session. Her enthusiasm cut through my fog. She asked me to assemble around 5,000 words of notes that she could show around inside her agency, and when the reception to that was good, she offered me rep and I signed with her. By this point, it was early summer 2025.
All through last summer and fall, I worked on the new proposal, fitting it in around a near FT reporting job and my son’s continuing frontline cancer treatment, offset by nearly 30 full luxurious minutes of childcare each week. The agent, her partner agent, and I all worked together to refine the material, and at least on my end, it took hundreds of hours, almost literally a month of Sundays. Last fall was an unusually beautiful fall and I didn’t hike once. I say this all to make clear that the experience was the opposite of glamorous. I lived on sugary triple espresso canned lattes from Target, and was in 7-11 buying Big Gulps often enough for the clerks to plead with me to join the loyalty program while I tried not to cry, screeching ARE YOU CRAZY I DON’T HAVE TIME! and DO I LOOK LIKE SOMEONE WHO CAN REMEMBER THEIR OWN PHONE NUMBER! Rarely has a season of my life been so packed with stress. Wall-to-wall with stress. Let’s come in and build an illegal ADU of stress here cause there’s not enough stress. We could Airbnb it out to earn a little more stress! Never-ending load.
By December, though, we were ready to go on submission, and by early January, we went to auction. We had interest and bids from huge names; the decision of who to go with was genuinely such a difficult one.
Now it’s just about a month later, the deal just got announced, and I truly could not be more thrilled to say that HELLO GORGEOUS MONSTER: MARY SHELLEY’S GUIDE TO STITCHING YOUR LIFE BACK TOGETHER is coming out from W.W. Norton in fall 2027.
Now, to get super explicit about what the Substack note and post helped with—the point of this post—here’s how I see it.
The note functioned as proof of audience and appetite. It didn’t have to go mega-viral to prove that people might want to read about Mary Shelley’s life or hear someone bash on Percy for 200 pages.
The note and the response to the note forced me to produce something—to move past private desktop mess to at least one public piece.
That public piece prompted the agent to reach out to me, setting the book project in motion.
It’s reasonable to ask: If I didn’t set out to sell a book this way, is it actually a good or reliable way to sell a book, one worth casually diagramming for others? But I think the experience is worth exploring FOR those reasons, not in spite of them. I hate publishing partial work. I hate publishing without an editor, just in general. But as the formal media ecosystem goes on dying, informal publishing—Substack and its ilk, “social media” and its ilk, notes, threads, posts, Instagram carousels, short-form video—becomes, well, all there is. The door. Whether you find an immediate audience for your ideas, or whether the labor is the slower and longer, the door.
Also, while I love a slow-baked piece of writing, a piece of writing that has spent time in the Great British Bakeoff proving drawer and now has many lovely layers and no soggy bottom, it can pay to publish before you’re ready, as I’ve said elsewhere.
Finally, the most helpful message in all this for me, at least, is seeing that all the small dumb daily failures—the notes that get no response, the long, carefully thought-out posts that net you fewer subscribers and not more—don’t really matter. Who pays attention to those? Mostly just you, the poster; otherwise they sink away. To be overly concerned with them isn’t necessary. One moonshot, however modestly or mildly moonshot-like, is worth thousands of tiny failures. What a relief, because day to day this whole writing thing mostly FEELS LIKE failure, or haven’t you noticed?? And the fear of just that sort of failure is with me now, even as I schedule this post. But you know what? It doesn’t even matter. Post imperfectly. Let things flop. Most things flop. The flops don’t matter. The moonshots do.
*Another reasonable question: how much did my previous book matter, or the fact that I’d met the agent online some years before?
I don’t think these things were meaningless or insignificant. At the same time, it’s not as if I was riding some big wave of career momentum at the moment I posted the original note—no, the opposite. I was barely working, and not posting much at all, because life was a blur of hospital stays and zoned-out dissociative recovery periods, staring at Netflix as if every show were in Thai and set on Mars. It had been six years since I signed my first deal. The sophomore slump is very, very real, and while I wish I could say different, in my experience it’s nearly as hard to break in the second time as it is the first.
And what helped me break in this time was a Substack note, then a Substack essay. I wouldn’t have believed it a year ago, so now I’m telling you: Hang in there, and think in public.
Thank you, as always, for reading. May all your poorly thought out efforts catch fire.
Cat
P.S. Can we be friends on Instagram? Maybe you’re a dozen years late to the party and not entirely clear on where your shit lives after you upload it too! In which case come sit next to me.



So happy for you! And this book is going to rock. Wishing your boy the best and you easy fun writing. Can’t wait to read your witty smart take!!
poe is happy for you too